Electronic Instrumentation

    The deflection sensitivity of a CRO is generally expressed in

• meter/V

• cm/V

• V/meter

• V/cm

   Assertion (A): The trigger circuit of a CRO is excited by the same signal as Y plates

Reason (R): The time base generator develops a sawtooth voltage

• A is true R is false

• Both A and R are true but R is not correct explanation of A

• Both A and R are true and R is correct explanation of A

• A is false R is true

  If E is the voltage applied to Y plates of CRO, then the vertical deflection of beam is proportional to

• E

If two-time varying signals of equal magnitudes and 90° (degree) phase displacement are applied to X and Y plates of CRO, the display will be

• A circle

• a rectangle

• an ellipse

• a straight line

     An oscilloscope has an input impedance consisting of 1 M-Ohm resistance and 20 pF capacitance are in parallel. A high impedence probe connected to input of this oscilloscope has a 10 M-Ohm series resistance. This 10 M-Ohm series resistance

•   should be shunted by 20pF capacitor

• should be shunted by 200 pF capacitor

• should be shunted by 2 pF capacitor

• may not be shunted

The time base of a high frequency CRO whose screen diameter is set at 10 micro-sec/cm. The lowest frequency which can be fully displayed on the screen is

• Equal to 10 kHz

• Less than 10 kHz

• More than 100 kHz

•   Equal to 100 kHz

  Loading effect is primarily caused by instrument having

• Low sensitivity

• High Sensitivity

• High Resistance

• High Range

    A digital multimeter can count from 0 to 9999. If the full scale reading is 9.999 V, the resolution of full scale reading is

• 1 mV

•    4.5 digit

• 0.001 mV

•   1000

A DSO can sample 10⁸ samples per second. The maximum frequency of a signal that can be monitored in this DSO is

• 1 kHz

•   10 kHz

• 50 MHz

•    100 MHz

A dual slope digital voltmeter uses a reference voltage of V_ref=4 V, while measuring an unknown voltage V_x, the integration time (when the integrator is connected to V_x) was 16 ms and the deintegration time (when the integrator is connected to -V_ref) was 32 ms. Then the value of V_x is

• 4 V

• 8 V

• 12 V

• 16 V